Production of ascorbic acid in plants

Abstract

The present invention relates to a polynucleotide in isolated form, which polynucleotide codes for a protein with the activity of the enzyme L-galactono-gamma-lactone dehydrogenase, which polynucleotide comprises at least the L-galactono-gamma-lactone dehydrogenase activity-determining parts of the coding part of the nucleotide sequence or a sequence derived therefrom on the basis of the degeneration of the genetic code. The invention further relates to the use of the polynucleotide in the production of transgenic plants, plant cells, or other eukaryotic cells.

What is claimed is:  
     
       1. An isolated or purified cDNA comprising SEQ ID NO:12 or fragment thereof encoding a polypeptide having L-galactono-γ-lactone dehydrogenase activity. 
     
     
       2. The isolated or purified cDNA as claimed in  claim 1 , consisting essentially of SEQ ID NO:12. 
     
     
       3. A recombinant expression vector comprising the isolated or purified cDNA of  claim 1 . 
     
     
       4. A recombinant expression vector comprising SEQ ID NO:12. 
     
     
       5. The recombinant expression vector of  claim 3  further comprising a polynucleotide coding for transcription and/or translation regulation factors. 
     
     
       6. The recombinant expression vector of  claim 3  further comprising a targeting sequence for targeting the encoded enzyme to various parts of a cell. 
     
     
       7. The recombinant expression vector of  claim 6 , wherein the parts of the cell are selected from the group consisting of: the cytoplasm, vacuoles, chloroplasts, mitochondria, lysosomes, endoplasmic reticulum, and Golgi apparatus. 
     
     
       8. An isolated or purified cDNA comprising SEQ ID NO:14 or fragment thereof encoding a polypeptide having L-galactono-γ-lactone dehydrogenase activity. 
     
     
       9. An isolated or purified polynucleotide encoding an amino acid sequence comprising SEQ ID NO:13 or a fragment thereof having L-galactono-γ-lactone dehydrogenase activity. 
     
     
       10. An isolated or purified polynucleotide encoding an amino acid sequence comprising SEQ ID NO:15 or a fragment thereof having L-galactono-γ-lactone dehydrogenase activity. 
     
     
       11. An isolated or purified cDNA comprising SEQ ID NO:12 or a fragment thereof encoding an amino acid sequence having L-galactono-γ-lactone dehydrogenase activity, with the proviso that said cDNA does not encode an amino acid sequence selected from the group consisting of: LTQAK; SKSPMSPAFSTA; DLYR; YTTEEALK; IEIPKDKEELEALQE; VNQAEAEF; DLEYIEQLK; DLCYIEQLK; YAPLDEDLHTVSNW; YLYIPYTDTVVVVT; NFNQPETLADLEALVK; VGWSXEELGFDXGGQQXV; VQQLVDAIQEYGL; EQQLGGLLQVGAXGTGA; YKENELNMGENS; and LKENELNMGENS. 
     
     
       12. The isolated or purified polynucleotide of  claim 8 , comprising SEQ ID NO:14. 
     
     
       13. A recombinant expression vector comprising the isolated or purified polynucleotide of  claim 8 . 
     
     
       14. A recombinant expression vector comprising SEQ ID NO:14. 
     
     
       15. The recombinant expression vector of  claim 13 , further comprising a polynucleotide coding for transcription and/or translation regulation factors. 
     
     
       16. The recombinant expression vector of  claim 13  further comprising a targeting sequence for targeting the encoded enzyme to various parts of a cell. 
     
     
       17. The recombinant expression vector of  claim 16 , wherein the parts of the cell are selected from the group consisting of: the cytoplasm, vacuoles, chloroplasts, mitochondria, lysosomes, endoplasmic reticulum, and Golgi apparatus. 
     
     
       18. An isolated or purified cDNA comprising SEQ ID NO:12 or a sequence derived therefrom on the basis of the degeneration of the genetic code. 
     
     
       19. An isolated or purified cDNA comprising SEQ ID NO:14 or a sequence derived therefrom on the basis of the degeneration of the genetic code. 
     
     
       20. An isolated or purified polynucleotide encoding an amino acid sequence comprising SEQ ID NO:13. 
     
     
       21. An isolated or purified polynucleotide encoding an amino acid sequence comprising SEQ ID NO:15. 
     
     
       22. The isolated or purified cDNA of  claim 8 , consisting essentially of SEQ ID NO:14.